The Effect of Maternal Warming During Cesarean Delivery on Neonatal Temperature

Maternal hypothermia during Cesarean delivery is predominately caused by a combination of neuraxial anesthesia and exposure of abdominal contents and skin to the low temperatures of the operating room (OR). Since maternal temperature and fetal temperature are intimately related, neonates experience hypothermia at birth due to maternal hypothermia. Neonatal hypothermia on admission to the Intensive Care Unit is an important determinant of morbidity and mortality, particularly in preterm neonates.

At BC Women's Hospital the majority of Cesarean deliveries are done under neuraxial anesthesia and the pediatricians have observed that some babies had suboptimal body temperatures at the time of Cesarean delivery. The pediatricians wanted to reverse this trend in neonatal hypothermia and requested that the OR temperature be increased to 25oC, more in line with World Health Organization (WHO) guidelines for delivery rooms. However, raising OR temperatures is usually not a comfortable option to the majority of staff working in this environment, therefore WHO recommendations are not followed.

Forced air warming is a common technique used during surgical procedures to maintain normothermia in anesthetized patients. A bi-layered blanket with multiple air channels is connected to a warming device that forces warm air between the layers of the blanket and ultimately around the patient. This device is effective in warming hypothermic patients or maintaining temperature in normothermic patients in a cool OR.

The studies on maternal warming at Cesarean delivery that have been published to date have shown inconsistent findings thus the subject warrants further investigation.

We postulate that actively warming mothers will prevent or decrease the risk of neonatal hypothermia at birth. In addition, we will examine whether active warming has a larger effect in the premature neonate.